Those are good flutes for the price indeed. I could not say about how much time would they last, because it's a pretty new brand in the market. But I've experimented many models and they are good step up instruments.
I actually own a DiZhao wood headjoint which fits perfectly to my Muramatsu EXIII. Sounds beautifully, at least to my taste of a wooden and warm tone.
One of my students purchased a 500 model. He is very happy with this flute.

But anyway there is a rule that applies to every new instrument purchase: try and try it!